Cantilever Sheet Pile Wall Design

Advantages of cantilever walls.

Cantilever sheet pile wall design.

The sheet piling is driven to a sufficient depth into the ground to become fixed as a vertical can tilever resisting a load from active earth pressure. The various forces acting on a cantilever sheet pile wall are the active earth pressure on the back of the wall and the passive earth pressure on the front of the wall. A cantilever sheet pile wall consists of sheet piling driven deep enough into the ground to become a fixed vertical cantilever. Figure 1 basic configuration with nomenclature of a cantilever sheet pile wall in a uniform soil in simple terms sheet piles are supported by the passive pressures below the dredge line offsetting either in overturning or sliding the active pressures on the earth side.

Please note this value is applied only for passive pressure. Cantilever walls offer an unbstructed open excavation. In general the maximum excavation for a cantilever wall can reach up to 6m or 18ft. Cantilever walls offer some advantages.

Design of cantilevered wall granular soil introduction. Because cantilever walls derive their support solely from the foundation soils they may be installed in relatively close proximity to existing structures. A sheet pile wall is required to support a 12 excavation. Deeper cantilever walls have been constructed but these required more expensive wall systems such as t type diaphragm walls.

Prosheet is a comprehensive sheet pile design software for cantilever and single supported retaining walls one anchor or strut. It covers every aspect of sheet pile design including the soil mechanics and earth pressure theory involved in sheet pile design structural considerations design of both cantilever and anchored walls earthquake design for sheet pile walls seepage and hydrostatic loads anchor systems and tiebacks cofferdams corrosion and more. It is based on the blum theory a limit equilibrium method lem. The civilweb cantilever sheet pile design excel spreadsheet is a powerful piece of design software which can be used to complete the calculations required for a sheet pile wall design in accordance with bs en 1997.

A cantilevered sheet pile wall performs somewhat like a cantilevered beam. It is a quite simple tool to determine all the forces required for designing a sheet pile retaining wall and ideal for preliminary designs. The soil is uniform as shown in the figure. The active pressure tends the wall to move away from the backfill while the passive earth pressure resists the wall movement.

Use factor of safety 1 5 for. Cantilever sheet pile walls cantilever walls are usually used as floodwall or as earth retaining walls with low wall heights 3 to 5 m or less. To take into account the friction between the wall and the soil we use friction angle δ φ 2. In a limit equilibrium analysis this type of wall is supported by a lateral earth pressure equal to the difference between the active and passive earth pressures above and below a point of rotation.